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The PulsaCoil BP shown schematically above is a very highly insulated appliance. As
such, the products will allow a pass to be achieved in SAP2005 even in small apartment
situations, which is to provide an improved method of supplying mains pressure hot
water when using a suitable off peak electric supply/tariff .
The heat losses from thermal stores should not be directly compared with heat losses
from unvented or vented cylinders because they are treated diff erently in SAP. The
SAP calculator takes account of the type of store and various correction factors are
included to refl ect the diff erent ways that the hot water and heating operates.
The main feature of the concept is that hot water can be supplied directly from the
mains at conventional fl ow rates without the need for temperature and pressure
relief safety valves or expansion vessels. This is achieved by passing the mains water
through heat exchangers inside the thermal store. The outlet temperature of the
domestic hot water is maintained by a thermostatic blending valve.
The Building Regulations L1A:
New dwellings/L1B: Existing dwellings and the
requirements set out in the Domestic Heating Compliance Guide specify that “where
the mains water hardness exceeds 200ppm provision should be made to treat the
feed water to water heaters and the hot water circuit of combination boilers to reduce
the rate of accumulation of lime scale”.
To comply with this requirement the hardness of the mains water should be checked
by the installer and if necessary the optional factory fi tted in-line scale inhibitor should
be specifi ed at the time of order for hardness levels between 200 and 300 ppm (mg/l).
Where the water is very hard ie 300ppm (mg/l)
and above the optional polyphosphate type,
scale inhibitor should be specifi ed at the time
of order. However, this will need to be fi tted by
the installer at a suitable point in the cold water
supply to the appliance.
Because this product does not require a safety
discharge from a temperature and pressure
relief valve, any installations will be easy to
incorporate into the building and will not suff er
from the problems associated with using PVCu
soil stacks to take the discharge from unvented
cylinders.
Figure 1.1
Schematic Hydraulic Arrangement
1. Bottom (Off-Peak) immersion heater
(1H_1)
2. Top (On-Peak) immersion heater (IH_2)
3. CW
inlet
4. HW outlet
5. Drain
6. Open vent
7. Cold feed
8. Top up cistern - provided separately
from the appliance
9. Thermostatic blending valve
Cistern can be provided with a
visual sight glass or ballvalve
and overflow connector as
optional extras if required.
Appliance
case
Top up cistern
PULSACOIL BP
9
5
4
3
6
8
7
2
1
DESIGN
INTRODUCTION
Summary of Contents for PulsaCoil PCBP 120
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